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Neurogenesis in adult primate neocortex: an evaluation of the evidence


Reports of continuous genesis and turnover of neurons in the adult primate association neocortex — the site of the highest cognitive functions — have generated great excitement. Here, I review the available evidence, and question the scientific basis of this claim.

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I am grateful to A. Alvarez-Buylla, V. Caviness, F. H. Gage, P. S. Goldman-Rakic, K. Herrup, D. R. Kornack, P. R. Levitt, E. Markakis, J. H. Morrison, E. Mugnaini, R. S. Nowakowski, D. Purves, N. Sestan and D. A. Steindler for their discussion and comments on the manuscript.

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Figure 1: Incorporation of 3H-dT as a marker of cell division.
Figure 2: Relationship between the time of origin and the final position of cortical neurons in the macaque monkey.
Figure 3: Satellite glia labelled with 3H-thymidine.
Figure 4: BrdU-labelled satellite glial cells.
Figure 5: Incorporation of exogenous nucleotides into nuclear DNA.
Figure 6: Endothelial cells might be misidentified as migrating cells.